@anonymoustroll420: strictly speaking it is not a blocksize increase. Stuff has been moved in another place to make room for other transactions.
As far as I know blocksize is the same and that's the reason for "2x or not 2x". But this is another story.
No, that is strictly false. Segwit is a block size increase; the size of a block message can be up to 4 MB now. 2x is yet another block size increase; it makes the maximum 8 MB.
To expand on that: Legacy nodes "perceive" SegWit blocks as staying within blocksize limitations, however the "physical" size of SegWit blocks can reach the aforementioned 4MB (ie. the "Stuff that has been moved in another place to make room for other transactions" is still part of the block, propagated over the network and stored in the blockchain, but ignored by legacy nodes).